Non-synchronous behavior of neuronal activity, oxidative metabolism and blood supply during mental tasks in man

Neurosci Lett. 1994 May 19;172(1-2):129-33. doi: 10.1016/0304-3940(94)90679-3.

Abstract

In near-infrared spectroscopic studies during mental tasks such as problem solving and mental arithmetic, we found that 9 of 33 healthy volunteers showed decreases in both the regional cerebral blood flow (r-CBF) and oxygen consumption rate (CMRO2) in the frontal region of the dominant hemisphere. To confirm these unexpected observations, we performed simultaneous measurements by positron emission tomography (PET) and near-infrared spectroscopy (NIRS) in two such subjects. PET images also showed that CBF decreased within the presumptive area illuminated by near-infrared light during mental task. However, CBF decreased in almost all regions while the subject gave a correct answer. Thus, the questions arose: Are mental tasks always associated with increases in r-CBF and/or CMRO2?

MeSH terms

  • Adult
  • Brain Chemistry / physiology
  • Cerebrovascular Circulation / physiology*
  • Female
  • Humans
  • Male
  • Mental Processes / physiology*
  • Middle Aged
  • Neurons / metabolism
  • Neurons / physiology*
  • Oxidation-Reduction
  • Oxygen Consumption / physiology*
  • Oxyhemoglobins / metabolism
  • Spectrophotometry, Infrared
  • Tomography, Emission-Computed

Substances

  • Oxyhemoglobins